New Enclosure Types For "Convertible" Laptops

When is a laptop not a laptop?

When it's a 2-in-1 convertible device or tablet with attached keyboard.  To this end you may now encounter devices whose Chassis Type is changed from "Notebook" to "Convertible" after a BIOS update.  This change is being driven by the SMBIOS 3.0 Specification which is an industry standard.

So why do we care?  In many cases enterprise admins tasked with deploying new PCs will make a distinction between a Laptop and a Desktop and apply different policies or software accordingly. For a laptop, the Win32_SystemEnclosure class might show a value of 9 (Laptop) or 10 (Notebook) for the ChassisTypes field. If these are the only values used with a WMI query to identify a laptop then you may miss some devices.

With the new SMBIOS 3.0 Specification you would want to add the following:
  • 30 - Tablet
  • 31 - Convertible
  • 32 - Detachable 
For example, the new ThinkPad Yoga 370 will have a value of 31 since it can convert from a Notebook form factor to a Tablet form factor by rotating its screen on the 360 degree Yoga hinge.
If you need to check the chassis type of a system you can run the following PowerShell command:

Get-WmiObject -Class Win32_SystemEnclosure | Select-Object -Property ChassisTypes


Note:  It has been noted that Windows 7 may not recognize the new values and will return a value of 2 ("Unknown"). So if you still are using Windows 7 you may need to take this into account.


  1. its good to see this blog..informative content.

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  2. WinPE from the Windows 10 1511 ADK recognizes the Chassis as a value of 2 ("Unknown").

    The Windows 10 1607 ADK and higher does not have this issue.

    Furthermore, the the ZTI_Gather.wsf script from the Microsoft Deployment Toolkit Build 8443 does not recognize the Chassis value of 31.

    Line 417 needs to be modified to the following for this for it to work correctly :

    Case "8", "9", "10", "11", "12", "14", "18", "21", "31"


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